Scraper for flowing wells



NOV. 24, 1931. w N 1,833,253

4 SCRAPER FOR FLOWING WELLS Filed Dec. 5, 1929 KM L Patented Nov. 24, 1931 UNITED STATES PATENT OFFIC Application filed December 5,1828. Serial No. 411,937.

This invention relates to means for scraping parafiine from the interior of a well casing in flowin wells. In many of the oil fields, especial y, for instance, in the Texas oil fields, parafline becomes very troublesome. In many of the big flowing wells as well as in the gas lift and pumping wells, pa'rafiine collects on the inside of the casing or tubing and stopsthe flow of oil and gas in a very few days.

The general object of the present invention is to provide a scraping tool adapted to be mounted on a connection of the drill stem or auger stem or otherwise which is so formed that as it is lowered downward inside of the casing or tubing, it will cut the parafline loose Without, however, in any way obstructing the free flow of the oil or gas so that the parafline may be flowed outwith the gas or lzltir, whichever is being used to flow the A further object is to provide a tool :of this character which has the form of a longitudinally twisted scraper or screw, the edges of the screw constituting cutting edges, the lower end of the tool being so formed that it will cut straight downward'through the parafline collected on the wall of the casing and will hold the scraper straight while it is cutting the arafiine. g

, A further 0 ject is to provide a scraper which is reversely twisted as regards its upper and lower portions so that when used in high pressure wells, it will prevent putting too much twist in thedrill cable.

If twist only in one direction were used, under these circumstances, the high pressure would cause the scraper to spin, but by pressure against the screw is balanced.

Other objects will appear in the course of the following description.

Myinvention isillustrated in the accom- I5 panying drawings, wherein Figure 1 is a longitudinal sectional view through a well casing showing my parafline remover applied thereto;

Figure 2 is an enlarged View of the paraf- 0 fine remover by itself and using a reverse twist or a double twist, the

Figure 3 is a section on the line 3 3 of Figure 2.

' Referring to the drawin s, A designates a well casing with the usua coupling B. C designates the auger or drillin stem to which my tool is attached and whic has the usual pin joint tothe drill jars D. Thesedrill jars at their upper ends are connected to the rope socket E. The lower end of the drill stem C is provided with the usual screw-threaded lsgcket. All of these parts are old and-well own.

My improved parafiine cutting tool consists terior of the casing. This scraping blade may have an overall length of between six and seven feet. At the lower end, the scraper blade 10 is formed to provide a portion 11 having a longitudinal straight edge 12 approximately eight inches long inactual practice, though it may have any desired length. The/lower end of the blade is beveled to form a cutting edge 13. This portion 11 has a width approximately that of the interior of the casin so that as'the scraper is lowered in the well, this straight edge 12 will cut into the parafiine lining the casing and this will hold the scraper from rotation while the parafline is being scraped ofl the casing and blade. Though I do not wish to be limited to this, the blade will-preferably have reverse twists, that is, the upper portion of the blade may have a right hand twist and the lower portion of the blade a left hand twist. The edges of the blade are sharply beveled so as to cut the parafiine from the inner face of the casing.

The upper end of the blade is square at 14 and above this is provided the collar 15 having the usual screw-threaded pins 16 whereby it may be connected into the socket at the lower end of the drill stem. lVhile in wells having low pressure, a scraper having a twist all in one direction may be used, yet I do not wish to be limited to this as in high pressure wells, it is desirable to provide a reverse] y twisted screw so that the pressure of gas, oil or air which is being'used to cause the well to flow will not tend, by its action upon the twisted blade, to turn the blade around axially and thus put too much twist on the drilling cable. By using the double twist, however, the pressure is equalized.

Preferably there is a little more twist on one portion of the scraper than on the other so as to keep a slight twist on the cable.-

In the use of this device, the sharp edges of the scraper cut the parafline loose and the flow of gas and. oil flows it out of the casing. The elongated lower port-ion 11 on' the lower end of the scraper enters the parafiine on the walls of the inner side of the casing and this tends to keep the scraper from turning, thus causing the sore er to remove the parafiine on the inside of t e casing and does not permit the scraper to rotate or out what 7 may be termed screw-threads in this parafline Without affecting the parafline.

With this parafline remover I have kept wells flowing for nearly a year steadily. If a drilling bit had been used to remove the parafiine, it would form a ball of paralline and kill the fiow of oil and gas. My device in no way impedes the flow of oil or gas,

, while at the same time fully cleans the walls of the well of parafiine.

' While I have illustrated certain details of construction and arrangements of parts, it will be understood that I do not wish to be limited to this except in so far as limited by the claims.

I claim 1. A parafiine remover of the character described, comprising a blade having portions I twisted in reverse directions, the blade having a width approximately equal to the interior diameter of a well casing with which it is used and having cutting edges, the lower end of the said blade having a transversely flat, longitudinally straight portion extending diametrically through the longitudinal axis of the twisted blade and having cutting edges adapted to form longitudinal cuts in the parafiine collected on the wall of the casing, this straight portion having a cutting edge at its'lower end.

2. Means for removing parafiine from the interior face of a well casing includin a drill jar, having means whereby it may supported from a cable, a drill stem engaged with the drill jar and a steeply twisted blade formed at its upper end for engagement with the drill stem, the blade having a width approximately equal to the interior diameter of the well casing with which it is to be used and having cutting edges and the lower end of the blade having a transversely fiat, longitudinally straight portion extending diametrically through theaxis of the twisted blade and having longitudinally straight edges adapted to form longitudinal cuts in the parafline lining the wall of the casing to therellzy hold the blade from rotation.

3. cans for removing paraffine from the interior face of a well casing includinga drill ar, having means whereby it may e sup: ported from a cable, a drill stem en aged with the drill jar and a steeply twisted lade formed at its upper end 'for engagement with the drill stem, the blade having a width approximately equal to the interior diameter of the well casing with which it is to be used and havin cutting edges and the lower end of the bla e having a transversely flat, longitudinally straight portion extending diametrically through the axis of the blade and having opposed longitudinally straight cut-- ting edges adapted to form longitudinal cuts in the parafiine linin the wall of the casing to thereby hold the b ade from rotation, the blade being twisted in reverse directions.

In testimony whereof I hereunto aflix my signature.

WILLIAM E. KEENAN. 

